In 2016, more than 250 million people were in migration around the world. This included not only refugees, asylum-seekers, and internally displaced persons (IDPs) but undocumented migrants, migrant workers, and survivors of human trafficking. While the contexts differ, as do specific programmatic and policy remedies, what unites these populations are the health and protection risks they face in their migration in vulnerable circumstances. But reconciling these different concepts and classifications can pose challenges for humanitarian actors.